In previous work supported by this grant (GM 16947), it has been shown that a variety of infectious agents, bacterial and viral, when present in vitro or in vivo, give rise to specific patterns of metabolic compounds in the culture medium or body fluid that permits the presumptive identification of each organism when the appropriate fluid is analyzed by gas chromatography (GC) under defined conditions. The purpose of this proposal is to extend these observations to assess the usefulness of these methods in the diagnosis of bacterial endocarditis, both human and experimental, in the epidemiologic investigation of pneumococcal pneumonia, both bacteremic and nonbacteremic, and in the management of tuberculosis. The use of GC and of mass spectrometry (MS) is planned to detect and to identify the specific metabolites of streptococcal, pneumococcal and mycobacterial strains in their specific culture media, and in the body fluids of the infected hosts. The further evaluation of GC patterns for the diagnosis of these diseases and the delineation of the critically important diagnostic GC peaks will be made in order to establish this technique as a useful tool in clinical pathology and in epidemiology.